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EWS
EWS III (3.3)
EWS III (3.3) is installed in the 1998 E38 from 5/97 production, in the 1998 E39 from 9/97
production, in the E46beginning of production, in the E52and E53 beginning of pro-
duction.
Purpose of the System
The purpose of the EWS III (3.3) system is to add greater theft protection by providing a
higher level of sophistication than previous systems. The new “Rolling Code” provides an
additional theft deterrent through a changing of the ISN everytime the vehicle enters the
start sequence.
Components changed in the EWS III (3.3) system include:
• EWS III (3.3) Control Module.
• DME Control Module.
• Transmission Range Selection Input.
System Components
EWS III (3.3) Control Module
The EWS III (3.3) Control Module uses the same 13 pin connector as EWS III (3.2) but func-
tions differently. The EWS III (3.3) module has a “Rolling Code” ISN assigned to it during
manufacture. The “Rolling Code” is burned into
the module and cannot be overwritten by ZCS
Coding or DME alignment procedures.
The “Rolling Code” is a one way signal from the
EWS III (3.3) control module to the DME and is
similar in operation to the data exchange
between the EWS control module and the key
transponder.
The “Rolling Code” will be different each time the
start operation is begun. The “Codes” are taken
from the “Rolling Code Table” which is assigned
at the factory to the EWS III (3.3) control module
and the DME.
8510133
Workshop Hint:
While it is possible to initialize a key to another
vehicle to check for remote operation, use cau-
tion. All keys for Bothvehicles must be avail-
able. The initializing process, causes loss of
operation of keys previously initialized.
All keys must be initialized at the same time.
